Dim a(4) As Integer

Private Sub Command1_Click()

 Dim s As String

a(1)=10:a(2)=30:a(3)=20:a(4)=40

 s=doit(4)

 Label1.Caption=s

End Sub

Function doit(k As Integer) As String

 If k=1 Then

  doit=Str(a(1))

  Else

  doit=doit(k-1) & Str(a(k))

 End If

End Function

程序运行后,标签Label1中显示的内容是（  ）

Function fg(n as Integer)As Integer

 If n=1 fg=1

 If n=2 fg=2

 If n>=3 fg=fg(n-1)+fg(n-2)

End Function

请问走完这8阶楼梯的走法有（  ）

Function fact(n As Integer) As String

If n = 1 Then

    fact = fact & 1

Else

    fact = fact(n \ 2) & n Mod 2

End If

End Function

Private Sub Command1_Click()

Dim x As String, i As Integer, r As Integer

x = Text1.Text

For i = 1 To Len(Text1.Text)

If Mid(x, i, 1) = "." Then Exit For Next i

r = Val(Mid(x, i + 1, Len(Text1.Text) - i)) Text2.Text = fact(r)

End Sub

在文本框Text1中输入2019.70，则执行程序段，在文本框Text2中显示的内容是（  ）

Private Sub Command1_Click()

  Dim y As Long

  Text1.Text = ""

  y = f(3)

  Label1.Caption = Str(y)

End Sub

Function f(n As Integer) As Long

    Text1.Text = Text1.Text + Str(n)

    If n <= 1 Then

       f = 1

    Else

       f = f(n - 1) + 2

    End If

End Function